crabs

Scylla serrata (Forskål, 1775)
Class Malacostraca Order Decapoda Infraorder Brachyura Family Portunidae
classification
mangrove crab
morphology surface substrate habitat
11 cm
image: Shane Ahyong
Carapace wider than long, surface very smooth, sides with nine sharp teeth behind eyes. Carapace
margin between eyes with six teeth; margin behind eyes with 9 spines. Large, smooth, powerful
chelipeds. Walking legs flattened and unspined. Last pair of legs flattened into rounded paddle,
fringed with setae. Swimming paddles with reticulated patterning. Variable but often olive/dark
green to very dark purplish. Chelipeds with brown fingertips. Very aggressive.
Estuaries in Northland. Occurs throught the tropical Indo-West Pacific. Burrows in mud of bays and
estuaries, espcially in mangrove areas. Intertidal-shallow subtidal.
It could also be……….
Nectocarcinus bennetti
Ovalipes catharus
Charybdis japonica
Keenan, C.P., Davie, P.J.F. & Mann, D.L. (1998) A revision of the genus Scylla de Haan, 1833 (Crustacea: Decapoda: Brachyura: Portunidae). Raffles Bulletin of
Zoology 46, 217-245.
Yaldwyn, J.C., Webber, R.W. (2011) Annotated checklist of New Zealand Decapoda (Arthropoda: Crustacea). Tuhinga 22: 171-272.
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